Effect of Abnormal Grains on the Mechanical Properties of FGH96 Solid-State Diffusion Bonding Joint

The hollow twin-web disk is designed to improve the thrust-to-weight ratio of aero engine, where welding joint microstructures determine disk’s mechanical properties. This study aimed elucidate effect abnormal grains formed in region on properties FGH96 solid-state diffusion bonding joints. Digital image correlation using images captured by scanning electron microscopy (SEM-DIC) and backscattering diffraction (EBSD) technologies were applied. results show that abnormally large (2.5 times matrix), with preferred orientation region, detrimental yield tensile strengths 995.85 MPa 1456.67 MPa, respectively, corresponding relative (ratio matrix) ones 92.54% 88.81%. After modifying process, grain size was tailored close matrix, considerable twin boundaries (TBs) formed, leading strength reaching 98.86% 99.37%. Furthermore, failure mode changed intragranular type from intergranular type. It demonstrates tailoring newborn size, introducing TBs inside, eliminating during process can be an efficient way